Phase shift circuit

Abstract

To provide a phase shift circuit capable of reducing loss.SOLUTION: A phase shift circuit includes: a distributing circuit for distributing an input signal to a first signal and a second signal having a different phase from the first signal; a first phase shifter for outputting a first output signal by shifting the phase of the first signal by a first angle; a second phase shifter for outputting a second output signal with a phase difference more than 0 degree and less than 90 degrees from the first output signal by shifting the second signal by a second angle in opposite direction from the first angle; a first amplifier for outputting a first amplified signal by amplifying the first output signal; and a second amplifier for outputting a second amplified signal by amplifying the second output signal, and connected to the first amplifier so as to synthesize the first amplified signal and the second amplified signal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a phase shift circuit. [Background technology]

[0002] Digital modulation methods are widely used in various multi-carrier communication systems such as wireless and satellite communications to improve communication capacity and achieve high data communication speeds. In digital modulation methods, information to be transmitted is modulated and then transmitted as part of both the amplitude and phase of a signal. Patent Document 1 discloses an electronic circuit that improves signal distortion that can degrade signal quality when transmitting such signals, and includes a phase difference distributor that shifts the phase of an input signal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-120037 Summary of the Invention [Problem to be solved by the invention]

[0004] The phase difference splitter included in the electronic circuit described in Patent Document 1 includes a 90-degree hybrid coupler that receives an input signal and splits the signal, and a phase shift circuit. The phase shift circuit includes a first line, a second line, and a resistor. One end of the first line is electrically connected to one end of the 90-degree hybrid coupler. One end of the second line is electrically connected to the other end of the 90-degree hybrid coupler. One end of the resistor is electrically connected to the other end of the first line, and the other end is electrically connected to the other end of the second line. That is, the phase difference splitter is configured by electrically connecting a resistor between one end of the 90-degree hybrid coupler, which is an in-phase output terminal, and the other end, which is an output terminal with a phase difference of 90 degrees. This enables the phase difference splitter to output a signal with a desired phase difference from the input signal.

[0005] However, in the phase difference splitter included in the electronic circuit described in Patent Document 1, a first signal flowing from the first line through a resistor to the second line and a second signal flowing from the second line through a resistor to the first line, which has an opposite direction to the first signal, cancel each other out, resulting in power loss.

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a phase shift circuit capable of reducing loss. [Means for solving the problem]

[0007] In order to achieve this object, a phase-shift circuit according to one aspect of the present invention comprises: a division circuit that divides an input signal into a first signal and a second signal having a phase different from that of the first signal; a first phase shifter that shifts the phase of the first signal by a first angle to output a first output signal; a second phase shifter that shifts the phase of the second signal by a second angle opposite to the first angle to output a second output signal having a phase difference from the first output signal that is greater than 0 degrees and less than 90 degrees; a first amplifier that amplifies the first output signal to output a first amplified signal; and a second amplifier that amplifies the second output signal to output a second amplified signal, the second amplifier being connected to the first amplifier so that the first amplified signal and the second amplified signal are combined. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a phase shift circuit capable of reducing loss. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a diagram illustrating an example of the configuration of a power amplifier circuit. [Figure 2] FIG. 2 is a diagram illustrating an example of the outline of the configuration of a phase shift circuit. [Figure 3] FIG. 2 is a diagram illustrating an example of a detailed configuration of a phase shift circuit. [Figure 4] 10 is a graph showing the relationship between signal loss and phase difference in a phase shift circuit. [Figure 5] FIG. 10 is a diagram showing a partial configuration of a phase shift circuit according to a first modified example. [Figure 6] FIG. 10 is a diagram showing a partial configuration of a phase shift circuit according to a second modified example. [Figure 7] FIG. 10 is a diagram showing a partial configuration of a phase shift circuit according to a third modified example. [Figure 8] 10 is a diagram illustrating an example of the configuration of a first phase shifter and a second phase shifter according to a modified example. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same elements are designated by the same reference numerals, and redundant description will be omitted.

[0011] ===Power Amplifier Circuit 10=== A power amplifier circuit 10 will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the power amplifier circuit 10. The power amplifier circuit 10 shown in Fig. 1 is mounted on a mobile communication device such as a mobile phone, and is used to amplify the power of a radio frequency (RF) signal to be transmitted to a base station.

[0012] The power amplifier circuit 10 amplifies the power of signals conforming to communication standards such as 2G (second generation mobile communication system), 3G (third generation mobile communication system), 4G (fourth generation mobile communication system), 5G (fifth generation mobile communication system), LTE (Long Term Evolution)-FDD (Frequency Division Duplex), LTE-TDD (Time Division Duplex), LTE-Advanced, LTE-Advanced Pro, and 6G (sixth generation mobile communication system). The frequency of the RF signal is, for example, approximately several hundred MHz to 100 GHz. However, the communication standards and frequencies of the signals amplified by the power amplifier circuit 10 are not limited to these.

[0013] The power amplifier circuit 10 includes, for example, a phase shift circuit 100, an input matching circuit 200, an intermediate matching circuit 300, an output matching circuit 400, and an output amplifier circuit 500.

[0014] The phase shift circuit 100 is a circuit that outputs a signal obtained by shifting the phase of the input signal RFin to a predetermined angle. The phase shift circuit 100 will be described in detail later.

[0015] The input matching circuit 200 is provided, for example, in the preceding stage of the phase shift circuit 100 and is a circuit that matches the impedance between the input terminal Tin and the phase shift circuit 100 .

[0016] The intermediate matching circuit 300 is provided in the subsequent stage of the phase shift circuit 100 and is a circuit that matches the impedance between the phase shift circuit 100 and the output amplifier circuit 500 .

[0017] The output matching circuit 400 is provided in the subsequent stage of the output amplifier circuit 500, and is a circuit that matches the impedance between the output amplifier circuit 500 and a circuit (not shown) in the subsequent stage of the output terminal Tout.

[0018] The output amplifier circuit 500 amplifies the signal output from the phase shift circuit 100 to produce an output signal RFout, which is output to the output terminal Tout via the output matching circuit 400 .

[0019] The phase shift circuit 100 and the output amplifier circuit 500 are configured to include bipolar transistors such as heterojunction bipolar transistors (HBTs). Note that the phase shift circuit 100 and the output amplifier circuit 500 may be configured to include field effect transistors (MOSFETs: Metal-oxide-semiconductor Field-Effect Transistors) instead of HBTs.

[0020] In the power amplifier circuit 10, the phase shift circuit 100 can reduce signal loss, and output the output signal RFout, which has been phase-shifted to a desired phase with respect to the input signal RFin, to the antenna.

[0021] Although FIG. 1 illustrates the case where the phase-shift circuit 100 is provided in the power amplifier circuit 10 including the single-stage output amplifier circuit 500, the present invention is not limited to this. For example, the power amplifier circuit 10 may be a power amplifier circuit including multiple amplifier stages, a differential amplifier circuit, a Doherty amplifier circuit, or the like.

[0022] ===Phase shift circuit 100=== <<Configuration Overview>> An example of the configuration of the phase shift circuit 100 will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the outline of the configuration of the phase shift circuit 100.

[0023] As shown in FIG. 2( a ), the phase shift circuit 100 includes, for example, a dividing circuit 110 , a first phase shifter 120 , a second phase shifter 130 , a first amplifier 140 , and a second amplifier 150 .

[0024] The phase shift circuit 100 combines two signals obtained by dividing the input signal RFin in the dividing circuit 110, the two signals having a phase difference greater than 0 degrees and less than 90 degrees, and outputs a signal with a desired phase.

[0025] The dividing circuit 110 divides the input signal RFin into a signal RF11 (first signal) and a signal RF12 (second signal) that is out of phase with the signal RF11. The dividing circuit 110 may be, for example, a circuit including a 90-degree hybrid circuit, a balun, a Wilkinson divider, or a Webb divider.

[0026] The first phase shifter 120 is a circuit that shifts the phase of the signal RF11 by a first angle and outputs a first output signal (hereinafter referred to as "signal RFφ"). In Fig. 2(a), the phase of the signal RFφ output from the first phase shifter 120 is indicated by "φ".

[0027] The second phase shifter 130 is a circuit that shifts the phase of the signal RF12 by a second angle opposite to the first angle, and outputs a second output signal (hereinafter referred to as "signal RFψ") whose phase difference with the signal RFφ is greater than 0 degrees and less than 90 degrees. In Figure 2(a), the phase of the signal RFψ output from the second phase shifter 130 is indicated by "ψ".

[0028] The second angle may be, for example, an angle having the same absolute value as the first angle and rotating in the opposite direction to the first angle. Specifically, for example, when the phase of signal RF11 is shifted 67.5 degrees (first angle) in the delay direction in the first phase shifter 120, the second phase shifter 130 may be configured to shift the phase of signal RF12 by 67.5 degrees (second angle) in the advance direction opposite to the delay direction. This facilitates the design of the phase shift circuit 100.

[0029] A phase difference greater than 0 degrees but less than 90 degrees refers to a phase difference greater than 0 degrees but less than 90 degrees in either the lead or lag direction, relative to either signal RFφ or signal RFψ. Specifically, if the phase of signal RFφ is 67.5 degrees in the lag direction and the phase of signal RFψ is 22.5 degrees in the lag direction, signal RFψ has a phase difference of 45.0 degrees in the lead direction relative to signal RFφ, which means the phase difference is greater than 0 degrees but less than 90 degrees. Similarly, if the phase of signal RFφ is 112.5 degrees in the lead direction and the phase of signal RFψ is 202.5 degrees in the lag direction, signal RFψ has a phase difference of 315.0 degrees in the lag direction relative to signal RFφ. In other words, since one signal cycle is 360 degrees, signal RFψ can be said to be 45.0 degrees in the lead direction relative to signal RFφ, which means the phase difference is greater than 0 degrees but less than 90 degrees.

[0030] The first amplifier 140 outputs a first amplified signal (hereinafter referred to as "amplified signal RFapφ") obtained by amplifying the signal RF11φ output from the first phase shifter 120. The output of the first amplifier 140 is electrically connected to the output terminal T2. A bias is supplied to the first amplifier 140 from a bias circuit (not shown). The first amplifier 140 includes a transistor. For example, the signal RF11φ is input to the base via a capacitor, the collector is electrically connected to the output terminal T2, and the emitter is electrically connected to a reference potential via a resistor.

[0031] The second amplifier 150 outputs a second amplified signal (hereinafter referred to as "amplified signal RFapψ") obtained by amplifying the signal RF12 output from the second phase shifter 130. The output of the second amplifier 150 is electrically connected to the output terminal T2. A bias is supplied to the second amplifier 150 from a bias circuit (not shown). The second amplifier 150 includes a transistor. For example, the signal RF12ψ is input to the base via a capacitor, the collector is electrically connected to the output terminal T2, and the emitter is electrically connected to a reference potential via a resistor.

[0032] That is, the output of the first amplifier 140 is electrically connected to the output of the second amplifier 150. Specifically, the output of the first amplifier 140 may be electrically connected to the output of the second amplifier 150 directly, or may be electrically connected to the output of the second amplifier 150 via a combiner (such as a balun) that combines signals. By electrically connecting the output of the first amplifier 140 to the output of the second amplifier 150 directly, the phase shift circuit 100 can avoid loss caused by the combiner.

[0033] As shown in FIG. 2(b), the phase shift circuit 100 outputs a signal (hereinafter referred to as "composite signal RFθ") having a phase indicated by vector θ. Vector φ indicates the signal magnitude of the amplified signal RFapφ output from the first amplifier 140 by its length, and the signal phase by its direction. Similarly, vector ψ indicates the amplified signal RFapψ output from the second amplifier 150.

[0034] In this way, the power amplifier circuit 10 can output an amplified signal of the desired phase from the output amplifier circuit 500 by shifting the phase of the input signal RFin using the distribution circuit 110, the first phase shifter 120, and the second phase shifter 130 in the phase shift circuit 100.

[0035] <<Configuration details>> Next, the detailed configuration of the phase shift circuit 100 will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is a diagram showing an example of the detailed configuration of the phase shift circuit 100. Fig. 4 is a graph showing the relationship between signal loss and phase difference in the phase shift circuit 100. In Fig. 4, the vertical axis represents the magnitude of signal loss (dB), and the horizontal axis represents the phase difference (deg) between signals RF11φ and RF12ψ.

[0036] The divider circuit 110 is, for example, a 90-degree hybrid circuit, and divides the input signal RFin into two signals with a phase difference of 90 degrees. 90 degrees includes cases where it is approximately 90 degrees, and includes, for example, a range of 70 degrees to 110 degrees. The divider circuit 110 includes quarter-wavelength electromagnetically coupled coupled lines 111 and 112, a terminal In, a terminal Iso, a terminal T0, and a terminal T90. The input signal RFin is input to the terminal In. A load (e.g., a 50Ω load) having the same magnitude as the characteristic impedance of the transmission line is connected to the terminal Iso. A -3 dB signal RF11 is output from the terminal T0 in phase with the input signal RFin. A -3 dB signal RF12 is output from the terminal T90 with a phase lag of 90 degrees relative to the input signal RFin.

[0037] The first phase shifter 120 is, for example, an n-type low-pass filter circuit, and is a circuit that delays the phase of the signal RF11 input via the terminal T0 (for example, the same phase as the input signal RFin).

[0038] Specifically, the first phase shifter 120 includes, for example, an inductor 121 (first inductor), a capacitor 122 (first capacitor), and a capacitor 123 (second capacitor). The inductor 121 is connected in series with the terminal T0 of the distribution circuit 110. The capacitor 122 has one end electrically connected to a node between the terminal T0 and one end of the inductor 121, and the other end electrically connected to a reference potential. The capacitor 123 has one end electrically connected to the other end of the inductor 121, and the other end electrically connected to the reference potential. In this way, the first phase shifter 120 is configured to include only one inductor, which enables the power amplifier circuit 10 to be miniaturized.

[0039] With this configuration, first phase shifter 120 outputs signal RF11φ, which is obtained by shifting the phase of signal RF11 input via terminal T0 in the delay direction ("-67.5 degrees" in FIG. 3), to first amplifier 140. Note that the phase delay angle of first phase shifter 120 is determined by the respective parameters of inductor 121, capacitor 122, and capacitor 123.

[0040] The second phase shifter 130 is, for example, a T-type high-pass filter circuit, and is a circuit that advances the phase of the signal RF12 input via a terminal T90 (for example, a phase delayed by 90 degrees from the phase of the input signal RFin).

[0041] Specifically, the second phase shifter 130 includes, for example, an inductor 131 (second inductor), a capacitor 132 (third capacitor), and a capacitor 133 (fourth capacitor). The capacitor 132 is connected in series to the terminal T90 of the distribution circuit 110. The capacitor 133 is connected in series with the capacitor 132. One end of the inductor 131 is electrically connected to a node between the capacitors 132 and 133, and the other end is electrically connected to a reference potential. In this way, the second phase shifter 130 is configured to include only one inductor, which enables the power amplifier circuit 10 to be miniaturized.

[0042] With this configuration, second phase shifter 130 outputs signal RF12ψ, which is obtained by shifting the phase of signal RF12 input via terminal T90 in the leading direction ("+67.5 degrees" in FIG. 3), to second amplifier 150. Note that the angle of phase lead of second phase shifter 130 is determined by the respective parameters of inductor 131, capacitor 132, and capacitor 133.

[0043] As a result, the phase shift circuit 100 can be miniaturized because it achieves phase shifting with a small number of inductors while reducing loss.

[0044] As a result of the above, the phase shift circuit 100 generates two signals, RF11φ and RF12ψ, whose phase difference is greater than 0 degrees and less than 90 degrees. Then, a composite signal RFθ, which is a combination of the amplified signals RFapφ and RFapψ, is output from the output terminal T2 of the phase shift circuit 100. The composite signal RFθ is a signal (in FIG. 3, the phase θ is "22.5 degrees") obtained by combining two signals whose phase difference is greater than 0 degrees and less than 90 degrees (for example, a phase difference of 45 degrees).

[0045] As shown in Fig. 4, the phase shift circuit 100 is preferably configured to combine two signals with a phase difference in the range of more than 0 degrees and less than 90 degrees, because signal loss associated with combining signals is small when the phase difference is less than 90 degrees. Furthermore, as shown in Fig. 4, signal loss increases when the phase difference exceeds 45 degrees, so the phase shift circuit 100 is preferably configured so that the phase difference between the two signals to be combined is approximately 45 degrees.

[0046] <<First Modification>> Next, a first modified example of the configuration of the phase shift circuit 100 will be described with reference to Fig. 5. Fig. 5 is a diagram showing the configuration of a portion of a phase shift circuit 100a according to the first modified example. Unless otherwise specified below, the configuration will be the same as that of the phase shift circuit 100.

[0047] The phase shift circuit 100a is a circuit in which the first phase shifter 120 in the phase shift circuit 100 is replaced with a first phase shifter 120a, and the second phase shifter 130 is replaced with a second phase shifter 130a.

[0048] The first phase shifter 120a is, for example, a T-type high-pass filter circuit, and is a circuit that advances the phase of the signal RF11 input via the terminal T0 (for example, the same phase as the input signal RFin).

[0049] Specifically, the first phase shifter 120a includes, for example, an inductor 121a (third inductor), a capacitor 122a (fifth capacitor), and a capacitor 123a (sixth capacitor). The capacitor 122a is connected in series to a terminal T0 of the distribution circuit 110. The capacitor 123a is connected in series with the capacitor 122a. One end of the inductor 121a is electrically connected to a node between the capacitors 122a and 123a, and the other end is electrically connected to a reference potential.

[0050] With this configuration, the first phase shifter 120a outputs to the first amplifier 140 a signal RF11φ obtained by shifting the phase of the signal RF11, which is in phase with the input signal RFin output from the terminal T0, in the leading direction ("+112.5 degrees" in FIG. 5).

[0051] The second phase shifter 130a is, for example, an n-type low-pass filter circuit, and is a circuit that delays the phase of the signal RF12 input via the terminal T90 (for example, a phase that lags behind the phase of the input signal RFin by 90 degrees).

[0052] Specifically, the second phase shifter 130a includes, for example, an inductor 131a (fourth inductor), a capacitor 132a (seventh capacitor), and a capacitor 133a (eighth capacitor). The inductor 131a is connected in series with a terminal T90 of the distribution circuit 110. One end of the capacitor 132a is electrically connected to a node between the terminal T90 and one end of the inductor 131a, and the other end is electrically connected to a reference potential. The capacitor 133a has one end electrically connected to the other end of the inductor 131a, and the other end is electrically connected to a reference potential.

[0053] With this configuration, the second phase shifter 130a outputs to the second amplifier 150 a signal RF12ψ obtained by shifting the phase of the signal RF12, which is delayed by 90 degrees in phase with the input signal RFin output from the terminal T90, in the delay direction ("-112.5 degrees" in Figure 5).

[0054] As a result, a composite signal RFθ is output from the output terminal T2 of the phase shift circuit 100a. The composite signal RFθ is a signal (phase θ is 22.5 degrees) obtained by combining two signals, amplified signal RF11apφ and amplified signal RFap12ψ, with a phase difference greater than 0 degrees and less than 90 degrees (in FIG. 5, the phase difference is 315 degrees, which is the same as a phase difference of 45 degrees).

[0055] As a result, the phase shift circuit 100a can be miniaturized because it achieves phase shifting with a small number of inductors while reducing loss.

[0056] <<Second Modification>> Next, a second modified example of the configuration of the phase shift circuit 100 will be described with reference to Fig. 6. Fig. 6 is a diagram showing the configuration of a portion of a phase shift circuit 100b according to the second modified example. Unless otherwise specified below, the configuration will be the same as that of the phase shift circuit 100.

[0057] The phase shift circuit 100b is a circuit in which the dividing circuit 110 in the phase shift circuit 100 is replaced with a dividing circuit 110a.

[0058] The dividing circuit 110a is, for example, a balun, and divides the input signal RFin into two signals with a phase difference of 180 degrees. 180 degrees includes cases where the difference is approximately 180 degrees, and includes, for example, a range of 145 degrees to 225 degrees. The balun is a coupling transformer that converts the unbalanced transmission line L1 into a balanced transmission line L2. The unbalanced transmission line L1 is formed in a spiral shape and is a line that transmits a change in potential relative to a reference potential. The balanced transmission line L2 is formed in a spiral shape and is a line that transmits a pair of signals that have equal amplitudes but are 180 degrees out of phase with each other. The dividing circuit 110a is configured so that the unbalanced transmission line L1 and the balanced transmission line L2 are electromagnetically coupled with each other in opposite polarity.

[0059] In the distribution circuit 110a, a signal RF11 with a phase that is 180 degrees ahead of the input signal RFin and at −3 dB is output from a terminal T11 to the first phase shifter 120. A signal RF12 with the same phase as the input signal RFin and at −3 dB is output from a terminal T12 to the second phase shifter 130.

[0060] As a result, the phase shift circuit 100b can be miniaturized because it achieves phase shifting with a small number of inductors while reducing loss.

[0061] <<Third Modification>> Next, a third modified example of the configuration of the phase shift circuit 100 will be described with reference to Fig. 7. Fig. 7 is a diagram showing the configuration of a portion of a phase shift circuit 100c according to the third modified example. Unless otherwise specified below, this will be considered to be the same as the phase shift circuit 100b.

[0062] The phase shift circuit 100c is a circuit in which the division circuit 110a in the phase shift circuit 100b is replaced with a division circuit 110b. The division circuit 110b is configured so that the unbalanced transmission line L1 and the balanced transmission line L2 are electromagnetically coupled with each other with the same polarity.

[0063] In the distribution circuit 110b, a signal RF11 of −3 dB in phase with the input signal RFin is output from a terminal T11 to the first phase shifter 120. A signal RF12 of −3 dB that is 180 degrees ahead of the input signal RFin is output from a terminal T12 to the second phase shifter 130.

[0064] As a result, the phase shift circuit 100c can be miniaturized because it achieves phase shifting with a small number of inductors while reducing loss.

[0065] <<Fourth Modification>> Next, a modified example of the first phase shifter 120 and the second phase shifter 130 will be described with reference to Fig. 8. Fig. 8 is a diagram showing an example of the configuration of the first phase shifter 120 and the second phase shifter 130 according to the modified example.

[0066] In the above description, the power amplifier circuit 10 has been described as including the first phase shifter 120 and the second phase shifter 130 each composed of one inductor and two capacitors, but is not limited to this. The first phase shifter 120 and the second phase shifter 130 may be configured to include at least one inductor and at least one capacitor.

[0067] Specifically, when the first phase shifter 120 and the second phase shifter 130 are high-pass filter circuits, they may be configured with two inductors and one capacitor, as shown in FIG. 8(a). In this case, the capacitor C10 is connected in series with a terminal (e.g., terminal T0) of the distribution circuit 110. One end of the inductor L10 is electrically connected to a node between terminal T0 and one end of the capacitor C10, and the other end is electrically connected to a reference potential. One end of the inductor L20 is electrically connected to the other end of the capacitor C10, and the other end is electrically connected to a reference potential.

[0068] Furthermore, when the first phase shifter 120 and the second phase shifter 130 are low-pass filter circuits, they may be configured with two inductors and one capacitor, as shown in FIG. 8(b). In this case, the inductor L30 is connected in series to a terminal (e.g., terminal T90) of the distribution circuit 110. The inductor L40 is connected in series with the inductor L30. The capacitor C20 has one end electrically connected to a node between the inductors L30 and L40, and the other end electrically connected to a reference potential.

[0069] <<Operation of the Phase Shift Circuit 100>> Next, an example of the operation of the power amplifier circuit 10 including the phase shift circuit 100 will be described with reference to FIGS.

[0070] 1, an input signal RFin is input to an input terminal Tin of a power amplifier circuit 10. The input signal RFin is input to a phase shift circuit 100 via an input matching circuit 200.

[0071] 2, phase-shift circuit 100 divides input signal RFin into signal RF11, which is in phase with input signal RFin, and signal RF12, which is 90 degrees out of phase with input signal RFin, using division circuit 110. Signal RF11 is input to first phase shifter 120. Signal RF12 is input to second phase shifter 130.

[0072] As shown in FIG. 3, the first phase shifter 120 outputs to the first amplifier 140 a signal RF11φ obtained by delaying the phase of the signal RF11 by 67.5 degrees.

[0073] The second phase shifter 130 outputs to the second amplifier 150 a signal RF12ψ, which is the signal RF12 with its phase advanced by 67.5 degrees.

[0074] The first amplifier 140 amplifies a signal RF11φ, which has a phase delayed by 67.5 degrees from the input signal RFin, and outputs the amplified signal RFapφ to a terminal T2.

[0075] The second amplifier 150 amplifies the signal RF12ψ, which has a phase delayed by 22.5 degrees from the input signal RFin, and outputs the amplified signal RFapψ to the terminal T2.

[0076] The phase shift circuit 100 then outputs from the terminal T2 a composite signal RFθ obtained by combining the amplified signals RFapφ and RFapψ and having a phase that is delayed by 22.5 degrees relative to the phase of the input signal RFin.

[0077] 1, the output amplifier circuit 500 receives the composite signal RFθ via the intermediate matching circuit 300. The output amplifier circuit 500 amplifies the composite signal RFθ to generate an output signal RFout, which is output from an output terminal Tout to an antenna (not shown).

[0078] This allows the power amplifier circuit 10 to output an output signal of a desired phase to the antenna with little power loss and using a miniaturized circuit.

[0079] ===Summary=== <1> The phase-shift circuit 100 according to an exemplary embodiment of the present disclosure includes a division circuit 110 that divides an input signal RFin into a signal RF11 (first signal) and a signal RF12 (second signal) having a phase different from that of the signal RF11 (first signal), a first phase shifter 120 that shifts the phase of the signal RF11 (first signal) by a first angle to output a signal RFφ (first output signal), and a second phase shifter 120 that shifts the phase of the signal RF12 (second signal) by a second angle opposite to the first angle to output a signal RFφ (first output signal) having a phase difference greater than 0 degrees. The phase shift circuit 100 includes a second phase shifter 130 that outputs a signal RFψ (second output signal) that is smaller than 90 degrees, a first amplifier 140 that amplifies the signal RFψ (first output signal) and outputs an amplified signal RFapψ (first amplified signal), and a second amplifier 150 that amplifies the signal RFψ (second output signal) and outputs the amplified signal RFapψ (second amplified signal), the second amplifier 150 being connected to the first amplifier 140 so that the amplified signal RFapψ (first amplified signal) and the amplified signal RFapψ (second amplified signal) are combined. This allows the phase shift circuit 100 to reduce loss associated with phase shifting.

[0080] <2> The first phase shifter 120 in the phase shift circuit 100 according to the exemplary embodiment of the present disclosure includes a first inductor (e.g., the inductor 121 in FIGS. 3, 6, and 7) connected in series with the distribution circuit 110, a first capacitor (e.g., the capacitor 122 in FIGS. 3, 6, and 7) having one end electrically connected to one end of the first inductor and the other end electrically connected to a reference potential, and a second capacitor (e.g., the capacitor 123 in FIGS. 3, 6, and 7) having one end electrically connected to the other end of the first inductor and the other end electrically connected to the reference potential. , and capacitor 123 in FIG. 7), and the second phase shifter 130 includes a third capacitor (e.g., capacitor 132 in FIGS. 3, 6, and 7) connected in series to the distribution circuit 110, a fourth capacitor (e.g., capacitor 133 in FIGS. 3, 6, and 7) connected in series with the third capacitor, and a second inductor (e.g., inductor 131 in FIGS. 3, 6, and 7) having one end electrically connected to a node between the third capacitor and the fourth capacitor and the other end electrically connected to a reference potential. <1> This allows the phase shift circuit 100 to be miniaturized because it realizes phase shifting with a small number of inductors while reducing loss involved in phase shifting.

[0081] <3> The first phase shifter 120a in the phase shift circuit 100 according to the exemplary embodiment of the present disclosure includes a capacitor 122a (a fifth capacitor) connected in series with the distribution circuit 110, a capacitor 123a (a sixth capacitor) connected in series with the capacitor 122a, and an inductor 121a (a third inductor) having one end electrically connected to a node between the capacitors 122a and 123a and the other end electrically connected to a reference potential. The second phase shifter 130a includes an inductor 131a (a fourth inductor) connected in series with the distribution circuit 110, a capacitor 132a (a seventh capacitor) having one end electrically connected to one end of the inductor 131a and the other end electrically connected to the reference potential, and a capacitor 133a (an eighth capacitor) having one end electrically connected to the other end of the inductor 131a and the other end electrically connected to the reference potential. <1> This allows the phase shift circuit 100 to be miniaturized because it realizes phase shifting with a small number of inductors while reducing loss involved in phase shifting.

[0082] <4> The second phase shifter 130, 130a in the phase shift circuit 100 according to the exemplary embodiment of the present disclosure shifts the phase of the signal RF12 (second signal) by a second angle that has an absolute value equal to the first angle and is opposite to the first angle, and outputs a signal RFψ (second output signal). <1> from <3> This makes it possible to easily design the phase shift circuit 100.

[0083] <5> The first phase shifter 120 and the second phase shifter 130 in the phase shift circuit 100 according to the exemplary embodiment of the present disclosure are configured to have a phase difference of 45 degrees. <1> from <4> The phase shift circuit according to any one of the above items 1 to 4, wherein the phase shift circuit 100a does not generate any loss due to the phase shift and realizes the phase shift with a small number of inductors, thereby enabling miniaturization.

[0084] <6> In the phase shift circuit 100 according to the exemplary embodiment of the present disclosure, the output terminal of the first amplifier 140 is electrically connected directly to the output terminal of the second amplifier 150. <1> from <5> In this manner, the phase shift circuit 100 can reduce loss by avoiding the occurrence of loss due to the combiner by electrically connecting the output of the first amplifier 140 directly to the output of the second amplifier 150.

[0085] <7> The dividing circuit 110 in the phase shifting circuit 100 according to an exemplary embodiment of the present disclosure is a 90-degree hybrid coupler. <1> from <6> The phase shift circuit according to any one of the above items 1 to 4, wherein the phase shift circuit 100 is capable of reducing loss involved in phase shifting.

[0086] <8> The dividing circuit 110 in the phase shifting circuit 100 according to an exemplary embodiment of the present disclosure is a balun. <1> from <6> The phase shift circuit according to any one of the above items 1 to 4, wherein the phase shift circuit 100 is capable of reducing loss involved in phase shifting.

[0087] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from its spirit, and equivalents are also included within the scope of the present invention. In other words, designs modified by those skilled in the art as appropriate are also encompassed within the scope of the present invention as long as they incorporate the characteristics of the present invention. For example, the elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those exemplified and can be modified as appropriate. Furthermore, the elements of the embodiments can be combined to the extent technically possible, and such combinations are also encompassed within the scope of the present invention as long as they incorporate the characteristics of the present invention. [Explanation of symbols]

[0088] 10...power amplifier circuit, 100...phase shift circuit, 110...distribution circuit, 120...first phase shifter, 130...second phase shifter, 140...first amplifier, 150...second amplifier, 200...input matching circuit, 300...intermediate matching circuit, 400...output matching circuit, 500...output amplifier circuit.

Claims

1. a dividing circuit that divides an input signal into a first signal and a second signal having a phase different from that of the first signal; a first phase shifter that shifts the phase of the first signal by a first angle to output a first output signal; a second phase shifter that shifts the phase of the second signal by a second angle opposite to the first angle, and outputs a second output signal whose phase difference with the first output signal is greater than 0 degrees and less than 90 degrees; a first amplifier that amplifies the first output signal and outputs a first amplified signal; a second amplifier that amplifies the second output signal and outputs a second amplified signal, the second amplifier being connected to the first amplifier so that the first amplified signal and the second amplified signal are combined; A phase shift circuit comprising:

2. The first phase shifter comprises: a first inductor connected in series to the dividing circuit; a first capacitor having one end electrically connected to one end of the first inductor and the other end electrically connected to a reference potential; a second capacitor having one end electrically connected to the other end of the first inductor and the other end electrically connected to a reference potential; Including, The second phase shifter comprises: a third capacitor connected in series to the dividing circuit; a fourth capacitor connected in series with the third capacitor; a second inductor having one end electrically connected to a node between the third capacitor and the fourth capacitor and the other end electrically connected to a reference potential; Including, 2. The phase shift circuit according to claim 1.

3. The first phase shifter comprises: a fifth capacitor connected in series to the dividing circuit; a sixth capacitor connected in series with the fifth capacitor; a third inductor having one end electrically connected to a node between the fifth capacitor and the sixth capacitor and the other end electrically connected to a reference potential; Including, The second phase shifter comprises: a fourth inductor connected in series to the dividing circuit; a seventh capacitor, one end of which is electrically connected to one end of the fourth inductor and the other end of which is electrically connected to a reference potential; an eighth capacitor, one end of which is electrically connected to the other end of the fourth inductor and the other end of which is electrically connected to a reference potential; Including, 2. The phase shift circuit according to claim 1.

4. the second phase shifter shifts the phase of the second signal by the second angle, which has an absolute value equal to that of the first angle and rotates in an opposite direction to the first angle, and outputs the second output signal.

2. The phase shift circuit according to claim 1.

5. the first phase shifter and the second phase shifter are configured so that the phase difference is 45 degrees; 4. The phase shift circuit according to claim 2 or 3.

6. an output terminal of the first amplifier is electrically connected directly to an output terminal of the second amplifier; 2. The phase shift circuit according to claim 1.

7. the dividing circuit is a 90-degree hybrid coupler; 2. The phase shift circuit according to claim 1.

8. The dividing circuit is a balun.

2. The phase shift circuit according to claim 1.

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